US Space Force X-37B Secert Spaceplane Returns to Earth After 434 Days in Space

The U.S. Space Force's secretive X-37B spaceplane has returned to Earth after a record-breaking 434-day mission, marking another milestone in the autonomous spacecraft’s evolving role in military and scientific research.

The reusable spaceplane, designated Orbital Test Vehicle-7 (OTV-7), touched down at Vandenberg Space Force Base on March 7, following its launch aboard a SpaceX Falcon Heavy rocket on December 28, 2023.

“Mission 7 broke new ground by showcasing the X-37B’s ability to flexibly accomplish its test and experimentation objectives across orbital regimes.” - Gen. Chance Saltzman, Chief of Space Operations

Advancing Aerobraking and Orbital Maneuvering

One of the mission’s most critical demonstrations was aerobraking, a technique that uses atmospheric drag to gradually alter a spacecraft’s orbit without expending large amounts of propellant. This method enables more efficient fuel usage while allowing for unpredictable orbital adjustments—an advantage that aligns with the Space Force’s focus on space domain awareness and strategic maneuverability.

Aerobraking allows the X-37B to make subtle trajectory changes without emitting telltale propulsion signatures, effectively providing a “stealth mode” for orbital repositioning. Such a capability is particularly useful in an era of increasing competition in space, where the ability to maneuver unpredictably can provide tactical advantages.

Expanding the X-37B’s Role in Space Operations

Beyond its classified military objectives, the X-37B program serves as a testbed for next-generation space technologies.

During OTV-7, the spacecraft hosted NASA experiments designed to study the effects of long-duration exposure to the space environment, as well as tests aimed at improving space domain awareness—the ability to track and characterize objects in orbit. These tests are expected to inform future spacecraft designs and enhance the Space Force’s capabilities in monitoring orbital activity across different altitudes and conditions.

While much of the X-37B’s mission profile remains classified, the Space Force has incrementally revealed more about the program’s contributions to space operations. The vehicle, developed by Boeing and managed in partnership with the Department of the Air Force Rapid Capabilities Office, continues to push the boundaries of autonomous spacecraft design and reusable space systems.

The Future of the X-37B Program

With each successive flight, the X-37B has demonstrated increasing endurance, adaptability, and operational versatility. Its ability to operate in multiple orbital regimes, conduct experiments, and return safely to Earth positions it as a key asset for the U.S. military’s expanding space capabilities.

The completion of Mission 7 raises questions about what the next flight might bring. Will future missions extend beyond the current record-breaking durations? Will the spacecraft be used for more advanced reconnaissance and counter-space operations? While official details remain sparse, one certainty is that the X-37B will continue to play a crucial role in shaping the future of military and scientific efforts in space.